Hotels seeking credit card details

Recently when booking a short break the Irish hotel looked for details of my credit card over the phone. Why do they do this? I can appreciate if the details are sought when actually checking in. Also in this general area i was told that one should not return to the hotel the plastic card issued for opening the room doors as it might contain data which might be passed on. Any truth in this?

the plastic card is programmed for a set period of time...i.e the duration of your stay.....it contains no personal details......and expires usually at 12 noon on the day of your departure date......
Usually Hotels ask for CC details in case of cancellation....in other words if a Hotel has a 48 hr cancellation policy and you cancel 24 hrs before arrival the Hotel will nearly always charge your CC for part or all of the room charge....
Thats my understanding of it...HTH

What Concio said is correct, credit card is for charging for no shows or late cancelations.
No date other than room no and date is on the keycards, the door locks of each room record when you enter the room.

Thanks for that..it is a relief to know the actual facts.

Actually last week I gave my cc details to a hotel over the phone, it was later used to bill food and accommodation for other rooms. The hotel rang me monday morn and have had problems with my card ever since (cant login into my MBNA and when i rang MBNA was told the card was lost/stolen).

Sandals, it sounds to me like your details were mistakenly used by Hotel....I'd imagine that the Hotel are liable then for the unauthorised charges...and I'd say you are probably better off cancelling that CC altogther and get a new one issued. This is extremely unprofessional and given the Hotel contacted you about it, they know they are in the wrong.....you might get a nice overnight or a dinner for 2 by way of apology if they have any marketing sense